Traveler ring assemblies



Oct. 2, 1962 A. E. BACKUS 3,056,250

TRAVELER RING ASSEMBLIES Filed April 13, 1959 2 Sheets-Sheet l ,22 l'fl' I INVENTOR.

In) l 12 ARIf/Z/RZ..5ALKU5 /V// I, BY 16 9 5 5 36' AZZ WZZLQ Oct. 2, 1962 A. E. BACKUS 3,056,250 TRAVELER RING ASSEMBLIES Filed April 15, 1959 2 Sheets-Sheet 2 1:17 5 45! 27 ,39 35 24 24 1 f 31 v I I I} l "H' UI, W If" fi .5. s 21 E /5? 22 1w i "X 55 13 n :1 I I ll!) L 5: a" i K .58 29 6 J 59 62 63 7 7 J6 W 6 5i 31 39 24 iii .57 4 m: 6/

2 I fix I 21 2 I l il' I ,1

ji 2 L. -1 7 INVENTOR.

9 AHTHZZRZEA'C/(Zls BY 5 mm 76 35b Z3 Z6 /5 it tfr 5022.

Patented Oct. 2, 1962 3,l56,250 TRAVELER RENE ASSEMBLIES ArthunE. Backus, Wheaten, lill., assignor to American Plasticraft Company, Chicago, TEL, a corporation of Illinois Filed Apr. 13, 1959, Ser. No. 805,373 15 Claims. ((31. 57-419) This invention relates to improvements in spinning and twisting traveler ring assemblies of the character used in r ng-spinning and similar frames in the production of textile thread or yarn and is concerned particularly to a novel assembly which requires no lubrication and in which the traveler guiding ring assembly is selectively adjustable in the mounting holder so as to facilitate easy mounting and removal of the traveler and/ or the traveler ring assembly when replacement is required, and to permit adjustment of the clearance between ring and traveler to suit varying conditions.

Present known types of traveler guiding rings were made in one piece mounted on or integral with a mounting holder. Such traveler rings are substantially rigid and non-deformable, thus presenting a situation that requires that the traveler be snapped over the ring and, when replacement is required, it must be broken or deformed to permit its removal. When a traveler is snapped onto a traveler ring, particularly one molded of a synthetic mate r al, it frequently happens that working surfaces of the ring are chipped, notched or otherwise marred to such extent that there is a tendency for the traveler, which is moved around the ring at a high rate of speed during machine operation, to flutter or chatter. As a result, the thread or yarn guided thereby is fed to the bobbin or quill in such manner as to wind non-uniformly. Such non-uniform winding places increased tension on the thread or yarn and often causes the thread or yarn to break, and results in rapid, non-uniform wear of the ring.

The structures disclosed herein, in several embodiments, are such as to overcome the foregoing and other disadvantages resulting from the use of prior known types of traveler ring assemblies. More particularly, the present structures embody novel means whereby the traveler may be easily and quickly mounted and removed without damage to the working surfaces of the traveler ring, or to the traveler. In the present structure, the traveler ring assembly may be moved quickly into various positions of adjustment so as to either enable a traveler to be mounted therein without snapping the same in place and be removed Without breakage. As a consequence, the traveler may be made smaller and of harder material having greater resistance to wear than has heretofore been possible and, in instances when a traveler of a different character is to replace another traveler to accommodate a different thread or yarn, the traveler or both the traveler and the ring mounting the same may be removed from the mounting holder without disturbing its adjustment relative to the machine, and the required replacements quickly installed. The instant structure is applicable to both vertical and horizontal type traveler rings interchangeably. The invention also includes the fabrication of the traveler mounting rings and holder from tough plastic material suitably reinforced to insure it retaining its requisite shape.

It is therefore an object of the present invention to provide a novel traveler ring and mounting holder as sembly.

Another object is to provide novel means for retaining a traveler ring in place in a mounting holder.

Another object is to provide a novelly constructed mounting holder for a traveler ring.

Another object is to provide a novel traveler ring assembly of a character to facilitate mounting and removal of a traveler thereon without deforming or breaking said traveler.

Another object is to provide a traveler ring which may be adjusted to reduce the clearance between ring and traveler to a minimum or to suit varying conditions.

Another object is to provide a traveler ring and holder therefor that is not expensive to manufacture, may be easily and quickly assembled and readily adjusted to mount or remove a traveler and which will remain in adjusted position during use and have long serviceable life.

The structure by means of which the above noted and other advantages of the invention are attained will be described in the following specification, taken in conjunction with the accompanying drawings, showing a preferred illustrative embodiment of the invention, in which;

FIG. 1 is a fragmentary plan view of a ring rail of a spinning frame showing a vertical traveler ring and mounting holder assembly embodying features of the invention.

FIG. 2 is an enlarged detail sectional view taken on line 2-2 of FIG. 1, showing the traveler ring assembly in collapsed condition.

FIG, 3 is a sectional view similar to FIG. 2, but showing the traveler ring assembly in expanded position and partly in elevation.

FIG. 4 is a fragmentary sectional view of the mounting holder showing the ring assembly collapsed, as in FIG. 1, and in elevation.

FIG. 5 is a sectional view of the mounting holder.

FIG. 6 is a central vertical sectional view of a mounting holder and a horizontal type of traveler ring, showing the ring partly in elevation and in collapsed position.

FIG. 7 is a similar sectional view of the structure shown in FIG. 6, showing the traveler ring partly broken away and in elevated position.

FIG. 8 is an elevational view of another ring assembly, partly in section, and showing the mounting holder in section.

FIG. 9 is an enlarged fragmentary sectional view of the mounting holder shown in FIG. 8.

Referring to the exemplary disclosures in the accompanying drawings and particularly to the embodiment illustrated in FIGS. 1 to 5, the traveler ring assembly, which comprises a pair of traveler rings 11 and 12, is mounted in a mounting holder 13 which is secured to the upper face of a ring-spinning frame rail 14. In practice, the rail 14- is of a length commensurate to the size of the spinning or twisting machine of which it is a part and is formed with a series of circular openings 15 over each of which is mounted one mounting holder 13. The mounting holder may have diametrically opposed lugs 16 integral therewith to receive mounting screws or bolts 17 for securing the mounting holder to frame 14.

The mounting holder may be fabricated from any suitable material capable of retaining its shape and preferably is made from suitable tough, wear resisting plastic material. It includes a base or mounting flange 18 carrying the lugs 16 and is formed with a circular opening 19 that is substantially concentric with rail opening 15. The circular opening 19 is surrounded by an upwardly extending perimeter flange 21 and a metal circular band 22 is bonded firmly around the base area of said perimeter flange and to mounting flange 18 to insure against distortion of the circular flanged opening 119.

As is perhaps best illustrated in FIGS. 1 and 5, the inside circumferential face of perimeter flange 21 is formed with two series of projections 23 and 24 respectively. The projections in each series are mutually spaced circumferentially, with the projections in one series offset circumferentially with respect to the projections of the other series susbtantially as shown. Projections 23 extend upwardly from the lower edge of perimeter flange 21 and terminate at their upper extremities in planular shoulders 25 each having stop lug 26 at one end. Projections 24 extend downwardly from adjacent to the upper edge of perimeter flange 21 and each terminates at one end in a planular shoulder 27. Each shoulder 27 extends but a part of the length of its projection 24 and terminates in an inclined edge 28 which merges with a stop shoulder 29 located at one end of a planular shoulder 31 positioned but a short distance below the top edge of each projection. As will be explained in detail presently, shoulders 25, 27 and 31 cooperate with the liner or traveler ring assembly 11, 12 now to be described.

Still referring to the FIGS. 1 to disclosure, the traveler ring assembly is comprised of the superposed liner rings 11 and 12, best shown in FIGS. 2, 3 and 4, and which preferably are fabricated from tough, wear resisting plastic material. Lower liner ring 12. consists of a circular body having an outside diameter to fit freely within perimeter flange 21 of mounting holde 13. A series of lugs 35 are formed integral with and are mutual- 1y spaced apart circumferentially on the outside circumferential face of liner 12 in a plane substantially midway between the top and bottom faces thereof. When the liner is in place within the mounting holder, lugs 35 are seated one on each planular shoulder and in endwise abutment with the related stop lugs 26. The bottom face of liner ring 12 terminates in an inwardly rolled circumferential flange 36, whereas its upper face is formed with a series of mutually spaced high lands 37 and low lands 38 joined at their related ends by inclined surfaces 39 defining a cam-like top surface.

Upper liner ring 11 has an upwardly inwardly inclined inner wall surface 41 which merges at its upper edge in an annular trough 42, the upper edge of which joins with the inner circular edge of an upwardly outwardly inclined top surface 43. A series of lugs 44 are formed integral with and are mutually spaced apart circumferentially on the outside circumferential face of liner ring 11. These lugs are adjacent to the bottom face of said liner ring which face is formed with a series of mutually spaced low lands 45 at each lug 44 and a series of high lands 46 joined at their related ends by inclined surfaces 47 so as to define a cam-like bottom surface.

When the liner rings 11 and 12 are in the position best shown in FIGS. 2 and 4, the opposed cam-like surfaces are mated and lugs 44 are in vertical register with and are seated on lugs 35. The liner rings are now in what might be termed a collapsed or traveler mounting condition and a traveler 48 may be mounted thereon or removed easily and quickly and without the aid of tools. The traveler 48 may be of any conventional shape adapted for mounting on the traveler ring assembly.

The traveler 48 illustrated is fabricated from metal rod stock having sufficient hardness to retain its shape and to resist bending or flexing, although it may be made of other suitable material such as tough wear-resisting plastic or ceramics. In either event, it is formed to include an intermediate traveler ring bridging portion 49 and substantially perpendicular upper and lower traveler engaging portions 51 and 52 respectively. The upper portion 51 has a downwardly turned end 53 and the terminal end of lower portion 52 is curved upwardly, as at 54, all for purposes to be described presently. When the liner ring assembly is in the collapsed position shown in FIGS. 2 and 4, the distance between the top face of upper liner 11 and the bottom face of lower liner 12 is substantially less than the distance between traveler end portions 53, 54, and the opposite traveler engaging portion 51 or 52, consequently the traveler 48 can be moved into place on the liner rings without forced springing and can be removed without breaking or deforming as is now commonly practiced when known types of traveler rings are used.

After traveler 48 has been fitted over the collapsed liner ring assembly, upper ring M is rotated in a clockwise direction, as viewed in top plan, so as to cause the mating cam-like faces to move relative to each other and elevate the upper liner ring 11 into the position substantially as shown in FIG. 3, wherein the distance between the upper surface of upper liner ring 1}. and the lower surface of lower liner ring 1 .2 is only slightly less than the distance between the ring engaging portions 51 and 52 of the traveler. When in this position, lugs 44 on said top liner ring have moved into engagement with the related shoulders 31 of mounting holder projections 24. Rotation is limited by abutment of said lugs 44 with stop shoulders 29 and ring 11 is frictionally held against reverse rotation by friction between its outside circumferential face and projections 24, or by other well knwon mechanical means. The traveler 48 is now held in place on the expanded liner ring assembly by engagement of its downturned end 53 over an external circumferential shoulder 55 on upper ring 11 and its upwardly curved terminal end 54 around the outside surface of the lower liner flange 36 and it is free to travel around the traveler ring assembly freely, silently and without chatter.

In the assembly shown in FIGS. 6 and 7, the mounting holder 13a is identical with the holder 13 previously described and like numbers are used to identify corresponding parts. The traveler mounting ring or liner 56 is made in one piece and it includes a circular body 57 having lugs 58 mutually spaced circumferentially on its outside lower margin. A relatively wide external flange 5'9 on its upper perimeter includes a rolled circumferential edge 61 and a downwardly inwardly inclined top surface 62. terminating on its inner edge in an internal bead 63. The liner ring is mounted within the peripherally flanged opening '19 of mounting holder 13a in such manner that it can be rotated a limited distance into either of the two positions of elevation shown in FIGS. 6 and 7. When held in the elevated position shown in FIG. 7, lugs 58 bear against the downwardly facing shoulders 31. With the ring in this position, a U-shaped traveler 64 may be slipped over or removed from perimeter flange 59, as shown in FIG. 7, owing to the presence of an annular gap 65 between said flange and the top edge of flange 21. By pressing down and rotating the liner ring 56 relative to the mounting holder, lugs 58 are carried downwardly along inclined surfaces 28 of projections 24a and come to rest between shoulders 27 on projections 24a and shoulders 25 on projections 23a and in abutment with stop lugs 26. When in this lowered position of use, as shown on FIG. 6, the gap 65 is eliminated and one terminal 66 of the traveler embraces the internal head 63 while its other terminal 6'7 overhangs external flange 59 and bears against the outside surface of the perimeter flange 21 on mounting holder 13a or against the lower surface of rolled circumferential edge 61 so as to prevent its displacement. It is evident from the foregoing that the traveler 64 can be mounted and removed Without the use of tools, breaking or deforming, or the likelihood of damaging the traveler mounting ring 56.

Referring now to the disclosure of a traveler ring assembly and mounting shown in FIGS. 8 and 9, the structure includes lower and upper traveler mounting rings or liners 11b and 1212 respectively, which are substantially like the liner rings 11, 12 described previously. In this embodiment, the cam surface 68-6-71 on ring Mb and the cam surface '72-73--74 on ring 12b co-act during relative rotation of said rings to raise or lower upper ring 11b so as to either retain a traveler in place on the ring assembly or permit its removal or placement. Thestructure of the mounting holder 7 6 is such that upper liner ring l lb may be turned clockwise or counterclockwise during adjustment. As best shown in FIG. 9, the mutually spaced projections 2512 are each formed with opposed stop lugs 26b between which the circumferentially spaced flange segments or lugs 35b on the bottom liner ring 1% are seated firmly. When the liner rings are in collapsed relationship the cam surfaces 6869-71 and 727374 thereof are mated and the circumferentially spaced flange segments or lugs 44b on the upper liner ring are seated on flange segments 35b. Rotary movement of the upper liner ring in either direction will carry flange segments 44b into abutment with a shoulder 3112 on each T-shape projection 77 which projections are mutually spaced circumferentially on the inside face of mounting holder 76. The vertical portions 78 of projections 77 act as stops to limit rotation of the upper liner ring in either direction. A liner of the general type shown in FIGS. 6 and 7 can also be used in holder 76, rotating in either direction to lock. Upward movement in locked position is prevented by T lug in holder and downward movement is prevented by contact between underside of liner flange 59 and top of holder 76. However, the lock lugs 58 on such liner would be located higher on the liner than shown in FIGS. 6 and 7.

Although I have described a preferred embodiment of my invention in considerable detail, it will be understood that the description thereof is intended to be illustrative, rather than restrictive, as many details of the structure shown may be modified or changed without departing from the spirit or scope of the invention. Accordingly, I do not desire to be restricted to the exact construction described.

I claim:

1. A spinning ring assembly comprising a mounting holder fabricated from plastic material and having a circular opening therein, an annular flange surrounding said opening and extending above the top plane of said holder, a reinforcing ring surrounding said flange, a plurality of projections on the inside surface of said flange, said projections being mutually spaced apart circumferentially and defining upwardly facing shoulders lying in a common plane, a traveler ring element mounted in said opening, external flange segments on the lower margin of said ring element seated on said shoulders, a cam surface on the upper edge of said ring element, a second traveler ring element seated in said opening above and concentric with the first named ring element, external flange segments on the lower margin of said second ring element normally seated on the external flange segments of the first ring element, a cam surface on the lower edge of said second ring element resting on the cam surface of the first named ring element, traveler bearing surfaces one on the other edge of each ring, a substantially U- shaped traveler bridging said rings and engaged at its ends around the respective bearing surfaces, said rings being rotatable relative to each other to move one toward and away from the other so as to retain the traveler in place thereon and permit its removal, and other mutually spaced projections on the inside surface of the flange to limit rotary and axial movement of the second ring element.

2. A spinning ring assembly comprising a mounting holder fabricated from plastic material and having a ciroular opening therein, an annular flange surrounding said opening and extending above the top plane of said holder, a reinforcing ring surrounding said flange, a plurality of projections on the inside surface of said flange, said projections being mutually spaced apart circumferentially and defining upwardly facing shoulders lying in a common plane, a traveler ring element mounted in said opening, external flange segments on said ring element and seated on said shoulders, a cam surface on the upper edge of said ring element, a second traveler ring element seated in said opening above and concentric with the first named ring element, external flange segments on the said second ring element normally seated on the external flange segments of the first ring element, a cam surface on the lower edge of said second ring element resting on the cam surface of the first named ring element, traveler bearing surfaces one on the other edge of each ring, and a substantially U-shape traveler bridging said rings and engaged at its ends around said respective bearing surfaces, said rings being rotatable relative to each other to move one toward and away from the other so as to retain the traveler in place thereon and to permit its removal.

3. A spinning ring assembly comprising a mounting holder fabricated from plastic material and having a circular opening therein, an annular flange surrounding said opening, means reinforcing said flange, a plurality of projections on the inside surface of said flange, said projections being mutually spaced apart circumferentially and each defining an upwardly facing shoulder, a traveler ring element mounted in said opening, external flange segments on the lower margin of said ring element seated on said shoulders, a second traveler ring element mounted in said opening with its lower edge in opposed relation to the upper edge of the first named ring element, external flange segments on said second ring element normally seated on the external flange segments of the first ring element, a cam surface on the opposed edges of said ring elements, traveler bearing surfaces one on the other edge of each ring, a traveler bridging said rings and engaged at its ends around the respective bearing surfaces, one of said rings being rotatable relative to the other and to the mounting holder to move one toward and away from the other so as to retain the traveler in place thereon and to permit its removal, and other mutually spaced projections on the inside surface of the flange to limit rotary and axial movement of the movable ring element.

4. A spinning ring asembly comprising a mounting holder having a circular opening therein, an annular flange surrounding said mounting, a plurality of projections on the inside surface of said flange, said projections being mutually spaced apart circumferentially and defining upwardly facing shoulders lying in a common plane, a traveler ring element mounted in said opening, external flange segments on said ring element seated on said shoulders, a cam surface on the upper edge of said ring element, a second traveler ring element seated in said opening above and concentric with the first named ring element, external flange segments on said second ring element normally seated on the external flange segments of the first ring element, a cam surface on the lower edge of said second ring element resting on the cam surface of the first named ring element, traveler bearing surfaces one on the other edge of each of said rings, a traveler bridging said rings and engaged at its ends around the respective bearing surfaces, said rings being rotatable relative to each other to'move one toward and away from the other so as to retain the traveler in place thereon and permit its removal, and other mutually spaced projections on the inside surface of the flange to limit rotary and axial movement of the second ring element.

5. A spinning ring assembly comprising a mounting holder having a circular opening therein, :an upstanding annular flange surrounding said opening, a plurality of projections on the inside surface of said flange, said projections being mutually spaced apart circumferentially and defining upwardly facing shoulders lying in a common plane, a traveler mounting ring mounted in said opening, external flange segments on said mounting ring seated on said shoulders, a cam surface on the upper edge of said mounting ring, a second traveler mounting ring seated in said opening above and concentric with said first named ring element, external flange segments on said second mounting ring, a cam surface on the lower edge of said second mounting ring resting on the cam surface of the first named mounting ring, a substantially U-shape traveler bridging said rings and having its ends extending over the other edges of said rings, said second mounting ring being rotatable relative to the first mounting ring to move said second ring toward and away from the other so as to prevent displacement of the traveler and to permit its removal, and other mutually spaced projections forming shoulders on the inside surface of the flange to limit rotary and axial movement of the second mounting ring.

6. A spinning ring assembly comprising a mounting holder having a circular opening therein, an annular flange surrounding said opening, a plurality of projections on the inside surface of said flange, said projections being mutually spaced apart circumferentially and defining upwardly facing shoulders lying in a common plane, a traveler mounting ring fitted into said opening, external flange segments on said ring and seated on said shoulders, a cam surface on the upper edge of said ring, a second traveler mounting ring seated in said opening above the first named ring, external flange segments on said second ring normally seated on the external flange segments of the first ring, a cam surface on the lower edge of said second ring seated on the cam surface of the first named ring, traveler bearing surfaces on the other edges of said rings, a substantially U-shape traveler bridging said rings and having its ends bridging the respective bearing surfaces and overlying the outside circumferential surfaces of said rings, said rings being rotatable relative to each other to move one toward and away from the other so as prevent separation of the traveler from said rings, and other mutually spaced projections on the inside surface of said flange to limit rotary and axial movement of the second ring.

7. A spinning ring assembly comprising a mounting holder having a circular opening therein, an upstanding flange surrounding said opening, a reinforcing backing for said flange, a pair of concentric traveler carrying rings mounted one upon the other and in said opening, mutually spaced circumferentially aligned shoulders on the inner circumferential face of the flange, and mutually spaced flange segments on the outside circumferential surface of at least the lower ring adapted to seat on said shoulders for supporting said rings in place.

8. A spinning ring assembly comprising a mounting having a circular opening therein, an upstanding flange surrounding said opening, a pair of concentric traveler carrying rings mounted one above the other in edge to edge abutment and in said opening, and complemental means on said rings and on said flange to retain the rings in said opening.

9. A spinning ring assembly of the character recited in claim 8, in which the rings have cam surfaces on their opposed edges to facilitate relative adjustment of said rings in the direction of their axis upon relative rotation of said rings.

10. In a spinning ring assembly including a mounting holder, a pair of traveler mounting rings arranged in edge to edge abutment one over the other concentrically and in said holder, said rings having mating cam surfaces on said abutted edges and being rotatable relative to each other so as to increase and decrease the combined thickness of said rings.

:11. In a spinning ring assembly including a mounting holder having a circular opening therein, a pair of traveler mounting rings mounted in said opening and one above the other edge to edge, said rings being concentric with each other and with the opening, means in the holder to support the lower mounting ring in said opening, and said rings having mating cam surfaces on said edges and being movable relative to each other so as to increase and decrease the combined thickness of said rings.

12. In a spinning ring assembly including a mounting holder having a circular opening therein, a traveler mounting ring arranged in said opening, means to support said ring in said opening, a second traveler ring seated in said opening and having its lower edge seated on the upper edge of said first traveler ring, and cam surfaces one on the upper edge of the first ring and one on the lower edge of the upper ring, said upper ring being rotatable relative to the lower ring and to the holder so as to be raised and lowered relative thereto.

13. A spinning ring assembly comprising a mounting holder having a circular opening therein, an upstanding annular flange surrounding said opening, a plurality of projections on the inside surface of said flange, said projections being mutually spaced apart circumferentially and defining upwardly facing shoulders lying in a common plane, a traveler mounting ring mounted on said opening, external flange segments on said ring seated on said shoulders, a cam surface on the upper edge of said ring element, a second traveler mounting ring seated in said opening above and concentric with the first named ring, external flange segments on said second mounting ring normally seated on the external flange segments of the first mounting ring, a cam surface on the lower edge of said second mounting ring resting on the cam surface of the first named mounting ring, a traveler bearing surface on the other edge of each of said rings, a substantially U-shape traveler bridging said rings and engaged at its ends around said bearing surfaces, said rings being rotatable relative to each other to move one toward and away from the other axially so as to retain the traveler in place thereon and to permit its removal, and other mutually spaced projections on the inside surface of the upstanding flange to limit axial movement of the second ring element in one direction, said last named projections having stop lugs vto limit rotation of the rotatable ring in either direction.

14. A spinning ring assembly comprising a mounting holder having a circular opening therein, an upstanding annular flange surrounding said opening, a plurality of upwardly facing shoulders on the inside surface of said flange, a first traveler mounting ring mounted concentrically in said opening, external flange segments on said mounting ring seated on said shoulders, a cam surface on the upper edge of said mounting ring, a second traveler mounting ring seated in said opening above and concentric with the first mounting ring, external flange segments on said second mounting ring, a cam surface on the lower edge of said second mounting ring normally seated on the cam surface of the first mounting ring, a traveler bearing surface on the other peripheral edge of each of said mounting rings, a substantially U-shape traveler bridging said rings and having its terminal portions overlying said bearing surfaces, said second mounting ring being rota table relative to the other to carry it toward and away from the other ring so as to engage and retain the traveler in place on said rings, and other mutually spaced T-shape projections on the inside surface of the flange to limit rotary and axial movement of the second mounting ring.

15. A spinning ring assembly comprising a mounting having a circular opening therein, an upstanding flange surrounding said opening, a pair of concentric traveler carrying rings mounted one above the other and in said opening, and shoulders on the inner circumferential face of the flange and complemental flange segments on the outside circumferential surfaces of the rings to retain the rings in said opening.

References Cited in the file of this patent UNITED STATES PATENTS 743,138 Booth Nov. 3, 1903 1,868,574 Hofmann July 26, 1932 1,957,041 Gilligan May 1, 1934 1,962,239 Gilligan June 12, 1934 2,533,503 Pimley Dec. 12, 1950 2,995,004 Ragan Aug. 8, 1961 

